Pseudo-haptic feedback takes advantage of a cross-modal integration between vision and haptics. Previous studies have shown that object stiffness can be rendered with pseudo-haptic feedback with external haptic inputs. This article explored whether the pseudo-haptic feedback was feasible with a mid-air action wherein no external haptic input was given. On each trial of the experiments, participants conduced a mid-air action to laterally move their hands as if they horizontally stretched an object in the display. In synchronized with the hands’ motion, the object horizontally deformed. The magnitude of the object deformation varied with the horizontal distance between participants’ hands (i.e., a hand distance). The ratio of deformation magnitudes to the hand distance (i.e., a deformation-to-distance ratio) was controlled; With a larger ratio, a smaller hand distance produced the maximum level of object deformation. The Poisson's ratio was also controlled; a higher Poisson's ratio produced a larger magnitude of vertical deformation. The participants were asked to report the stiffness of the objects with a five-point rating scale. Consequently, the stiffness rating decreased with the deformation-distance ratio and with the Poisson's ratio. The results indicate that pseudo-haptic stiffness can be rendered with mid-air action by manipulating the deformation-distance ratio and Poisson's ratio.

中文翻译：

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空中动作有助于伪触觉刚度效应

伪触觉反馈利用了视觉和触觉之间的跨模式集成。先前的研究表明，可以通过具有外部触觉输入的伪触觉反馈来呈现对象刚度。本文探讨了在不提供外部触觉输入的空中动作中，伪触觉反馈是否可行。在每次实验中，参与者都会进行一次空中动作，横向移动他们的手，就好像他们水平拉伸显示器中的一个物体一样。与手的运动同步，物体水平变形。物体变形的大小随着参与者手之间的水平距离（即手距）而变化。控制变形量与手距的比值（即变形与距离的比值）；以较大的比例，较小的手距产生最大程度的物体变形。泊松比也得到控制；较高的泊松比会产生较大的垂直变形量。参与者被要求用五点评分量表报告物体的刚度。因此，刚度等级随着变形距离比和泊松比而降低。结果表明，通过操纵变形距离比和泊松比，可以通过空中动作呈现伪触觉刚度。参与者被要求用五点评分量表报告物体的刚度。因此，刚度等级随着变形距离比和泊松比而降低。结果表明，通过操纵变形距离比和泊松比，可以通过空中动作呈现伪触觉刚度。参与者被要求用五点评分量表报告物体的刚度。因此，刚度等级随着变形距离比和泊松比而降低。结果表明，通过操纵变形距离比和泊松比，可以通过空中动作呈现伪触觉刚度。